Problem: How many significant figures does $0.857610$ have?
Explanation: Identify the non-zero digits and any zeros between them. These are all significant. $0.{85761}0$ Leading zeros are not significant. $\color{orange}{0.}{85761}0$ Since there is a decimal, trailing zeros are significant. $\color{orange}{0.}{857610}$ Counting all the significant digits gives us 6.